_decodeJ2K(frameIndex = 0) {
let encodedPixelData = DicomParser.readEncapsulatedPixelData(this._dataSet, this._dataSet.elements.x7fe00010, frameIndex);
// let pixelDataElement = this._dataSet.elements.x7fe00010;
// let pixelData = new Uint8Array(this._dataSet.byteArray.buffer, pixelDataElement.dataOffset, pixelDataElement.length);
let jpxImage = new Jpx();
// https://github.com/OHIF/image-JPEG2000/issues/6
// It currently returns either Int16 or Uint16 based on whether the codestream is signed or not.
jpxImage.parse(encodedPixelData);
// let j2kWidth = jpxImage.width;
// let j2kHeight = jpxImage.height;
let componentsCount = jpxImage.componentsCount;
if (componentsCount !== 1) {
throw 'JPEG2000 decoder returned a componentCount of ${componentsCount}, when 1 is expected';
}
let tileCount = jpxImage.tiles.length;
if (tileCount !== 1) {
throw 'JPEG2000 decoder returned a tileCount of ${tileCount}, when 1 is expected';
}
let tileComponents = jpxImage.tiles[0];
let pixelData = tileComponents.items;
// window.console.log(j2kWidth, j2kHeight);
return pixelData;
}
_decodeJPEGBaseline(frameIndex = 0) {
let encodedPixelData = DicomParser.readEncapsulatedPixelData(this._dataSet, this._dataSet.elements.x7fe00010, frameIndex);
let rows = this.rows(frameIndex);
let columns = this.columns(frameIndex);
let bitsAllocated = this.bitsAllocated(frameIndex);
let jpegBaseline = new JpegBaseline();
jpegBaseline.parse(encodedPixelData);
if (bitsAllocated === 8) {
return jpegBaseline.getData(columns, rows);
} else if (bitsAllocated === 16) {
return jpegBaseline.getData16(columns, rows);
}
}
// from cornerstone
_decodeJPEGLossless(frameIndex = 0) {
let encodedPixelData = DicomParser.readEncapsulatedPixelData(this._dataSet, this._dataSet.elements.x7fe00010, frameIndex);
let pixelRepresentation = this.pixelRepresentation(frameIndex);
let bitsAllocated = this.bitsAllocated(frameIndex);
let byteOutput = bitsAllocated <= 8 ? 1 : 2;
let decoder = new Jpeg.lossless.Decoder();
let decompressedData = decoder.decode(encodedPixelData.buffer, encodedPixelData.byteOffset, encodedPixelData.length, byteOutput);
if (pixelRepresentation === 0) {
if (byteOutput === 2) {
return new Uint16Array(decompressedData.buffer);
} else {
// untested!
return new Uint8Array(decompressedData.buffer);
}
} else {
return new Int16Array(decompressedData.buffer);
}
}